How to build a fence

Planning the size, look, and positioning of your fence is very important and will save you time and trouble later on. It means you can be accurate with all the materials you need, saving on cutting and wastage. If your fence is marking a property boundary, we recommend you talk to your neighbours first and let them know your plans. Questions to ask yourself:

• Does an existing fence need to be removed first? 
• Whose property is it on, yours or your neighbours'?
• Do you need access to their garden to install your fence?

In most cases, you don’t need planning permission to construct a fence less than 2m high, but it’s best to check with your local planning authority if you’re unsure of restrictions.

On the other hand, you may need planning permission if your fence borders a public right-of-way.

Check the area for any cables or pipes underground to ensure it’s safe to proceed.

Begin unscrewing and levering the panels away from the posts, stacking them safely to either be recycled or disposed of.

Remove any brackets, rails, screws or nails that are still attached to the remaining posts.

To remove the posts, dig around them to expose their bases and any concrete footing. Loosen the post by rocking it back and forth until it’s ready to pull out. You can then break up or take out the concrete if required.

Put each material type into a pile to be recycled or disposed of.

Fill any holes in the ground with soil or hardcore and compact the ground.

If you’re building a garden fence in the back garden, it can be up to 2m (6.6 feet) tall, but in the front garden, you can’t surpass 1m (3.3 feet).

Fence panels are usually 6 feet in length, but there are other varieties available on the market.

To ensure a successful fence installation, you’ll need the following equipment and materials:

• CAT detector (for scanning underground services)

• Bamboo poles

• String line

• Tape measure

• Pencil or marker

• Spirit level

• Timber offcuts (for checking post height alignment)

• Spade or post hole digger

• Shovel

• Wheelbarrow (optional, for soil, gravel, and waste)

• Gardening fork (optional, for compacted ground)

• Gloves

• Rake (for clearing debris)

• Containers or bags for relocating plants/shrubs

• Fence posts (correct length for fence + trellis if applicable)

• Gravel or MOT Type 1 

• Postcrete

• Water (for Postcrete, if required by manufacturer)

• Timber battens (for propping posts)

• Screws for battens

• Screwdriver or drill/driver

• L brackets (for gravel boards)

• U brackets (for fence panels and trellis)

• 20mm external-grade screws (for gravel boards)

• 35mm external-grade screws (for fence panels and trellis)

• Fence panels

• Pressure-treated gravel boards

• Trellis panels (if needed)

• Handsaw or circular saw for cutting

• Clamps (optional, for securing panels while cutting)

• Workbench or sawhorse

• Square or straight edge (for accurate cuts)

• Trowel (for shaping Postcrete slope)

• Post caps

• Drill bits (including wood bits for pre-drilling post caps)

• Safety glasses

• Ear protection (if using power tools)

• Knee pads

• Weatherproof wood treatment (for cut ends)

Once you have scanned the area for cables and marked out the fence line with bamboo poles and string, you’re ready to install your new fence. Remove any rocks or debris from the area and carefully dig up any small plants or shrubs that you want to replant once the fence is in position.

Mark out the position of your first fence post and dig a hole appropriate to the length of the post you’re using. As previously mentioned, a standard hole would be 450-600mm deep and 300mm wide. If you’re digging into soft ground, you may need a deeper hole and a longer post.

Add roughly 25mm of gravel or MOT type 1 to the bottom of the hole. This’ll help with drainage and reduce the chance of the post rotting over time.

Place your first fence post into the hole, and use a spirit level to position the post, making sure that it’s vertically level on two adjacent sides. At this point, it helps to screw two timber battens to the post to temporarily secure it in position.

Following the manufacturer’s instructions, carefully add Postcrete to the hole. You should fill the hole until the Postcrete is 25mm beneath the surface line, making sure your fence post stays level the entire time.

Use a trowel to create a gentle slope in the Postcrete so that rainwater will run away from the fence post on all sides. Once the Postcrete has set, you can remove the timber props.

Repeat the above process until all the fence posts are securely in place, checking as you go that each one is exactly vertical.

As you go along, lay a piece of timber across the top of two consecutive posts and use a spirit level to check that the posts are level. If necessary, trim the tops of the posts down so they’re all the same height.

If your fence panels are dip-treated, protect them from rot by installing pressure-treated gravel boards. Start by marking the position of an L bracket onto the base of each fence post and then fix the L bracket to the post and secure the gravel boards to the L bracket with 20mm screws.

Mark out the positions of two U brackets to the inside of each post - one 150mm from the top and one 150mm from the bottom of where the fence panel will be. Secure the brackets with 35mm external grade screws.

With the help of another person, carefully lift the fence panels into position, sliding them down between the U brackets. Secure the panels in position with 35mm external grade screws.

This depends on the complexity of the fence configuration and your abilities. It can take anywhere from 1 to 5 days.

You’ll often need to trim a fence panel to fit a required space. Firstly, measure out the section you need, and mark a saw guideline. Then remove the framing battens from the front and back of the section you will be cutting.

If you reattach the battens to the new marked edge, you can also use them as a secure guideline for sawing. Make sure you saw the panel flush with the outer edge of the repositioned batten. You may also need to reposition the centre battens too.

Measure and mark where on the fence post the trellis will be positioned and fix a U bracket to the posts. The number of brackets you need may depend on local conditions. You’ll need more brackets in a particularly exposed or windy location.

Slide the trellis into position and secure it using 35mm external-grade screws. Repeat this process until all your trellis is attached.

To add a neat finish to your fence posts, you can protect them by adding a post cap. Pre-drill a hole into the top of the fence post before screwing the cap in place.